#include <fcntl.h>
#include <getopt.h>
#include <inttypes.h>
+#include <limits.h>
#include <errno.h>
#include <locale.h>
#include <time.h>
struct bsx64 *pbsx = &ppbr->bsx;
unsigned int i;
- /* Fill exfat BIOS paramemter block */
+ /* Fill exfat BIOS parameter block */
pbpb->jmp_boot[0] = 0xeb;
pbpb->jmp_boot[1] = 0x76;
pbpb->jmp_boot[2] = 0x90;
memcpy(pbpb->oem_name, "EXFAT ", 8);
memset(pbpb->res_zero, 0, 53);
- /* Fill exfat extend BIOS paramemter block */
- pbsx->vol_offset = 0;
+ /* Fill exfat extend BIOS parameter block */
+ pbsx->vol_offset = cpu_to_le64(bd->offset / bd->sector_size);
pbsx->vol_length = cpu_to_le64(bd->size / bd->sector_size);
pbsx->fat_offset = cpu_to_le32(finfo.fat_byte_off / bd->sector_size);
pbsx->fat_length = cpu_to_le32(finfo.fat_byte_len / bd->sector_size);
/* fs_version[0] : minor and fs_version[1] : major */
pbsx->fs_version[0] = 0;
pbsx->fs_version[1] = 1;
+ pbsx->phy_drv_no = 0x80;
memset(pbsx->reserved2, 0, 7);
memset(ppbr->boot_code, 0, 390);
ppbr->signature = cpu_to_le16(PBR_SIGNATURE);
+ exfat_debug("Volume Offset(sectors) : %" PRIu64 "\n",
+ le64_to_cpu(pbsx->vol_offset));
exfat_debug("Volume Length(sectors) : %" PRIu64 "\n",
le64_to_cpu(pbsx->vol_length));
exfat_debug("FAT Offset(sector offset) : %u\n",
if (is_backup)
sec_idx += BACKUP_BOOT_SEC_IDX;
- ppbr = malloc(sizeof(struct pbr));
+ ppbr = malloc(bd->sector_size);
if (!ppbr) {
exfat_err("Cannot allocate pbr: out of memory\n");
return -1;
}
- memset(ppbr, 0, sizeof(struct pbr));
+ memset(ppbr, 0, bd->sector_size);
exfat_setup_boot_sector(ppbr, bd, ui);
goto free_ppbr;
}
- boot_calc_checksum((unsigned char *)ppbr, sizeof(struct pbr),
+ boot_calc_checksum((unsigned char *)ppbr, bd->sector_size,
true, checksum);
free_ppbr:
static int exfat_write_extended_boot_sectors(struct exfat_blk_dev *bd,
unsigned int *checksum, bool is_backup)
{
- struct exbs eb;
+ char *peb;
+ __le16 *peb_signature;
+ int ret = 0;
int i;
unsigned int sec_idx = EXBOOT_SEC_IDX;
+ peb = malloc(bd->sector_size);
+ if (!peb)
+ return -1;
+
if (is_backup)
sec_idx += BACKUP_BOOT_SEC_IDX;
- memset(&eb, 0, sizeof(struct exbs));
- eb.signature = cpu_to_le16(PBR_SIGNATURE);
+ memset(peb, 0, bd->sector_size);
+ peb_signature = (__le16*) (peb + bd->sector_size - 2);
+ *peb_signature = cpu_to_le16(PBR_SIGNATURE);
for (i = 0; i < EXBOOT_SEC_NUM; i++) {
- if (exfat_write_sector(bd, &eb, sec_idx++)) {
+ if (exfat_write_sector(bd, peb, sec_idx++)) {
exfat_err("extended boot sector write failed\n");
- return -1;
+ ret = -1;
+ goto free_peb;
}
- boot_calc_checksum((unsigned char *) &eb, sizeof(struct exbs),
+ boot_calc_checksum((unsigned char *) peb, bd->sector_size,
false, checksum);
}
- return 0;
+free_peb:
+ free(peb);
+ return ret;
}
static int exfat_write_oem_sector(struct exfat_blk_dev *bd,
unsigned long long offset)
{
int nbyte;
+ off_t fat_entry_offset = finfo.fat_byte_off + (offset * sizeof(__le32));
- lseek(fd, finfo.fat_byte_off + (offset * sizeof(__le32)), SEEK_SET);
- nbyte = write(fd, (__u8 *) &clu, sizeof(__le32));
+ nbyte = pwrite(fd, (__u8 *) &clu, sizeof(__le32), fat_entry_offset);
if (nbyte != sizeof(int)) {
exfat_err("write failed, offset : %llu, clu : %x\n",
offset, clu);
for (i = 0; i < finfo.used_clu_cnt - EXFAT_FIRST_CLUSTER; i++)
exfat_set_bit(bd, bitmap, i);
- lseek(bd->dev_fd, finfo.bitmap_byte_off, SEEK_SET);
- nbytes = write(bd->dev_fd, bitmap, finfo.bitmap_byte_len);
+ nbytes = pwrite(bd->dev_fd, bitmap, finfo.bitmap_byte_len, finfo.bitmap_byte_off);
if (nbytes != finfo.bitmap_byte_len) {
exfat_err("write failed, nbytes : %d, bitmap_len : %d\n",
nbytes, finfo.bitmap_byte_len);
ed[2].upcase_start_clu = cpu_to_le32(finfo.ut_start_clu);
ed[2].upcase_size = cpu_to_le64(EXFAT_UPCASE_TABLE_SIZE);
- lseek(bd->dev_fd, finfo.root_byte_off, SEEK_SET);
- nbytes = write(bd->dev_fd, ed, dentries_len);
+ nbytes = pwrite(bd->dev_fd, ed, dentries_len, finfo.root_byte_off);
if (nbytes != dentries_len) {
exfat_err("write failed, nbytes : %d, dentries_len : %d\n",
nbytes, dentries_len);
static void usage(void)
{
- fprintf(stderr, "Usage: mkfs.exfat\n");
- fprintf(stderr, "\t-L | --volume-label=label Set volume label\n");
- fprintf(stderr, "\t-c | --cluster-size=size(or suffixed by 'K' or 'M') Specify cluster size\n");
- fprintf(stderr, "\t-b | --boundary-align=size(or suffixed by 'K' or 'M') Specify boundary alignment\n");
- fprintf(stderr, "\t-f | --full-format Full format\n");
- fprintf(stderr, "\t-V | --version Show version\n");
- fprintf(stderr, "\t-v | --verbose Print debug\n");
- fprintf(stderr, "\t-h | --help Show help\n");
+ fputs("Usage: mkfs.exfat\n"
+ "\t-L | --volume-label=label Set volume label\n"
+ "\t-c | --cluster-size=size(or suffixed by 'K' or 'M') Specify cluster size\n"
+ "\t-b | --boundary-align=size(or suffixed by 'K' or 'M') Specify boundary alignment\n"
+ "\t --pack-bitmap Move bitmap into FAT segment\n"
+ "\t-f | --full-format Full format\n"
+ "\t-V | --version Show version\n"
+ "\t-v | --verbose Print debug\n"
+ "\t-h | --help Show help\n",
+ stderr);
exit(EXIT_FAILURE);
}
-static struct option opts[] = {
+#define PACK_BITMAP (CHAR_MAX + 1)
+
+static const struct option opts[] = {
{"volume-label", required_argument, NULL, 'L' },
{"cluster-size", required_argument, NULL, 'c' },
{"boundary-align", required_argument, NULL, 'b' },
+ {"pack-bitmap", no_argument, NULL, PACK_BITMAP },
{"full-format", no_argument, NULL, 'f' },
{"version", no_argument, NULL, 'V' },
{"verbose", no_argument, NULL, 'v' },
{NULL, 0, NULL, 0 }
};
+/*
+ * Moves the bitmap to just before the alignment boundary if there is space
+ * between the boundary and the end of the FAT. This may allow the FAT and the
+ * bitmap to share the same allocation unit on flash media, thereby improving
+ * performance and endurance.
+ */
+static int exfat_pack_bitmap(const struct exfat_user_input *ui)
+{
+ unsigned int fat_byte_end = finfo.fat_byte_off + finfo.fat_byte_len,
+ bitmap_byte_len = finfo.bitmap_byte_len,
+ bitmap_clu_len = round_up(bitmap_byte_len, ui->cluster_size),
+ bitmap_clu_cnt, total_clu_cnt, new_bitmap_clu_len;
+
+ for (;;) {
+ bitmap_clu_cnt = bitmap_clu_len / ui->cluster_size;
+ if (finfo.clu_byte_off - bitmap_clu_len < fat_byte_end ||
+ finfo.total_clu_cnt > EXFAT_MAX_NUM_CLUSTER -
+ bitmap_clu_cnt)
+ return -1;
+ total_clu_cnt = finfo.total_clu_cnt + bitmap_clu_cnt;
+ bitmap_byte_len = round_up(total_clu_cnt, 8) / 8;
+ new_bitmap_clu_len = round_up(bitmap_byte_len, ui->cluster_size);
+ if (new_bitmap_clu_len == bitmap_clu_len) {
+ finfo.clu_byte_off -= bitmap_clu_len;
+ finfo.total_clu_cnt = total_clu_cnt;
+ finfo.bitmap_byte_off -= bitmap_clu_len;
+ finfo.bitmap_byte_len = bitmap_byte_len;
+ return 0;
+ }
+ bitmap_clu_len = new_bitmap_clu_len;
+ }
+}
+
static int exfat_build_mkfs_info(struct exfat_blk_dev *bd,
struct exfat_user_input *ui)
{
+ unsigned long long total_clu_cnt;
int clu_len;
+ if (ui->cluster_size < bd->sector_size) {
+ exfat_err("cluster size (%u bytes) is smaller than sector size (%u bytes)\n",
+ ui->cluster_size, bd->sector_size);
+ return -1;
+ }
if (ui->boundary_align < bd->sector_size) {
exfat_err("boundary alignment is too small (min %d)\n",
bd->sector_size);
return -1;
}
- finfo.fat_byte_off = round_up(24 * bd->sector_size,
- ui->boundary_align);
- finfo.fat_byte_len = round_up((bd->num_clusters * sizeof(int)),
- ui->cluster_size);
- finfo.clu_byte_off = round_up(finfo.fat_byte_off + finfo.fat_byte_len,
- ui->boundary_align);
+ finfo.fat_byte_off = round_up(bd->offset + 24 * bd->sector_size,
+ ui->boundary_align) - bd->offset;
+ /* Prevent integer overflow when computing the FAT length */
+ if (bd->num_clusters > UINT32_MAX / 4) {
+ exfat_err("cluster size (%u bytes) is too small\n", ui->cluster_size);
+ return -1;
+ }
+ finfo.fat_byte_len = round_up((bd->num_clusters * 4), ui->cluster_size);
+ finfo.clu_byte_off = round_up(bd->offset + finfo.fat_byte_off +
+ finfo.fat_byte_len, ui->boundary_align) - bd->offset;
if (bd->size <= finfo.clu_byte_off) {
exfat_err("boundary alignment is too big\n");
return -1;
}
- finfo.total_clu_cnt = (bd->size - finfo.clu_byte_off) /
- ui->cluster_size;
- if (finfo.total_clu_cnt > EXFAT_MAX_NUM_CLUSTER) {
+ total_clu_cnt = (bd->size - finfo.clu_byte_off) / ui->cluster_size;
+ if (total_clu_cnt > EXFAT_MAX_NUM_CLUSTER) {
exfat_err("cluster size is too small\n");
return -1;
}
+ finfo.total_clu_cnt = (unsigned int) total_clu_cnt;
finfo.bitmap_byte_off = finfo.clu_byte_off;
finfo.bitmap_byte_len = round_up(finfo.total_clu_cnt, 8) / 8;
+ if (ui->pack_bitmap)
+ exfat_pack_bitmap(ui);
clu_len = round_up(finfo.bitmap_byte_len, ui->cluster_size);
finfo.ut_start_clu = EXFAT_FIRST_CLUSTER + clu_len / ui->cluster_size;
}
ui.boundary_align = ret;
break;
+ case PACK_BITMAP:
+ ui.pack_bitmap = true;
+ break;
case 'f':
ui.quick = false;
break;